A gyratory crusher has a crushing head on which a substantially conical inner shell is mounted. An outer shell is mounted in a crusher frame in such a manner that it surrounds the inner shell, a crushing gap being formed between the inner shell and the outer shell. In the course of the crushing operation, the crushing head, and thereby the inner shell, executes a gyratory pendulum movement, which causes a material, for example rock, that is introduced in the crushing gap to be crushed into smaller size.
It is often desirable to be able to feed as much material as possible into a gyratory crusher without overloading the crusher. WO 2005/007293 discloses a method of controlling a gyratory crusher to obtain a high load without overloading the crusher. In the method disclosed in WO 2005/007293 instantaneous loads on the crusher are measured and a mean value is calculated, which is representative of the highest instantaneous loads. This mean value, which may be designated as the mean peak pressure, is used to control the crusher to allow feeding of a large amount of material without overloading the crusher. An indicating instrument indicates whether the operation of the crusher is effective or not by comparing the mean peak pressure and the mean pressure. However, it would be desirable to find a way to further increase the amount of material that can be fed to the crusher without overloading it.